The 742 carbine is a short barrel version of the 742 rifle. The gas port is in the same location near the breach. The only problems I have seen with this model is improper cleaning and shooting light bullets. Mine would jam every time with accelerators and a lot with hand-loads under 140 grains when velocities were topped out. It seems the carbine barrel is too short to allow proper gas expansion to cycle the action before the pressure drop when the bullet exits the barrel. These same loads did fine in the rifle or when loaded slower. If shooting 165 grains or higher in factory loads or equivalent hand-loads and proper cleaning is observed then have a gunsmith who works on gas operated rifles to check out the gas system and bolt lockup.
Depends on who made it.
100-400 USD
Look hereWhat_is_the_value_of_a_Remington_Model_742_in_good_condition
You can go to Remington's web site and request a owner's manual.
100-300 USD
The extractors break, particularly if shooting the "accelerator" bullets.
$400- $500, built between 1960-19070
Carbine version - 6 1/2 lbs Rifle version - 7 1/2 lbs
You can't shoot reloads in the 742 or it will jam. My guess is they expand just enough to jam. When I first got mine 18 years ago I had the same problem. Since then I only shoot with new shells.
742 40/4 = 752= 742 + 40/4= 742 + 10= 752
742 multiplied by 4 is 2,968.
742-349 = 393